Producing scrambled eggs having a homogeneous firmness at high volumes without channeling or fouling cooking equipment or damaging heating equipment as a result of the fouling has been a problem. During the initial heating of the eggs with a heat exchanger such as a scraped surface heat-exchanger, egg has fouled the heat exchanger even to the extent of breaking the heat exchanger blades.
Holding tubes where liquid egg is held at elevated temperatures to cook the eggs develop “channeling”. This is where laminar flow develops, as egg thickens and/or coagulates at the outer boundaries of the holding tube but tends to stay liquid at the center. In this circumstance egg, flows faster through the center of the holding tube than at the outer perimeter, and as a result, develops a center channel. This creates a product which is not evenly cooked. For instance, egg flowing through the center channel tends to be undercooked, resulting in a watery or mushy egg product. At the same time, egg at the outer boundaries of the holding tube tends to be overcooked, resulting in very small pieces. The typical approach for minimizing laminar flow and eliminating large distributions of residence time in a hold tube is to induce turbulent flow. Turbulence is usually induced by creating high flow velocities or by providing mechanical shear (e.g. in a screw extrusion cooker). This is not acceptable in the production of scrambled egg product, however, as the solid and partially coagulated egg is very shear sensitive, as excessive shear leads to a finely granulated product with poor mouth feel.